It is well known to provide fluid dispensers for use in restaurants, factories, hospitals, bathrooms and the home. These dispensers may contain one of a number of products such as, for example, soap, anti-bacterial cleansers, disinfectants, lotions and the like. The dispensers may include some type of pump actuation mechanism where the user pushes or pulls a lever to dispense a quantity of fluid, as is known in the art. Alternatively, “hands-free” automatic dispensers may also be utilized where the user simply places one or both hands underneath a sensor and a quantity of fluid is dispensed. Similar types of dispensers may be used to dispense powder or aerosol materials.
Product dispensers are commonly configured to be mounted on to a wall or other vertical surface, with the product being dispensed from an outlet near the bottom of the dispenser. It is also known that dispensers may be integrated into a countertop near a sink basin, with certain components of the dispensing system being located beneath the countertop, and other components, including an outlet, being located above the countertop. These types of dispensers are often referred to as counter-mount dispensing systems. Various other configurations of dispensers are also known, including table-top style dispensers that rest on a horizontal surface such as a counter or table top, or stand mounted dispensing systems that attach to a mounting pole.
Dispensers may directly hold a quantity of product, but these bulk fill dispensers have been found to be both messy and difficult to service. Bulk fill systems may also pose contamination and health concerns. As a result, refill units or containers that hold a quantity of fluid and provide a pump and nozzle mechanism have become increasingly popular. The sanitary refill units or containers are advantageous in that they are easily installed and replaced and create virtually no mess.
For varying reasons, manufacturers of product dispensers and refill units commonly wish to control the type of refill put in a dispenser. It is often of concern that the correct refill unit (type of product, concentration, product form, etc.) is put in the correct dispenser housing. In many cases, installing the correct refill unit is crucial to the customer. For example, it is imperative to hospital personnel to have anti-bacterial soap dispensed in a pre-surgical cleaning area, rather than another fluid such as, for example, moisturizing lotion. Therefore, manufacturers often provide keyed nozzle and pump mechanisms for each type of fluid refill unit so that only the appropriate refill unit can be installed in corresponding fluid dispensers. Manufacturers and associated distributors also rely upon keying systems to ensure that the dispensers can only be refilled with their own products and not products that may be inferior or have poor quality.
Conventional mechanical keying systems typically include a key projecting from one of the refill unit or the dispenser housing, and a keyway in the other adapted to receive the key. Insertion of the refill unit into the dispenser is prevented unless the key and keyway match. While these types of keying systems have proven somewhat successful, they also suffer from several disadvantages. The keys, in many cases, may simply be broken off or otherwise removed to bypass the keying system, especially where a competitor product is being used. In addition, the materials used to form the keys often allow the incorrect key to deform enough to fit within a dispenser. Furthermore, once the keying mechanism is bypassed to allow the refill unit to be fully inserted into the housing it operates as intended, with no further obstacles to overcome.
Thus, there is a need for an improved keying system for dispensers that alleviates one or more of the disadvantages of the prior art.